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Purpose of Review: The purpose of this review is to highlight recent developments in the Doppler assessment of the fetal venous circulation with special reference to clinical applications in the human fetus., Recent Findings: Doppler evaluation of the fetal venous circulation has increased our understanding of fetal cardiovascular function. Examples include the regulatory role of the ductus venosus in fetal nutrient partitioning and the significance of venous and arterial circulatory watershed areas. Alterations in cardiac afterload, contractility compliance, intravascular volume status and heart rate modulate venous and arterial flow velocity waveforms. Concurrent examination of these cardiovascular factors is of great importance in fetal growth restriction, complicated monochorionic multiple gestation, fetal hydrops and arrhythmia. In these conditions, comprehensive Doppler assessment provides critical diagnostic and prognostic information and has a key role in directing interventions., Summary: Venous Doppler has added a critical dimension to the understanding of fetal cardiovascular pathophysiology. In both health and disease, venous Doppler must now occupy a fundamental position in the comprehensive assessment of the fetal circulation.

Purpose of Review: Doppler applications in pregnancy are expanding exponentially. Flow velocity waveforms provide important information 12 weeks to term, from maternal vessels, placental circulation and fetal systemic vessels, with implications for both mother and fetus. As applications proliferate, awareness of the complexity of fetal and placental circulations, in normal pregnancy and in sequential responses to compromise, has also grown. The necessary data are now available to establish core values in Doppler evaluation for at-risk pregnancies., Recent Findings: Uterine arteries depict maternal vascular effects of the invading placenta, predicting the frequency and severity of pre-eclampsia and intrauterine growth restriction. New evidence suggests early treatment based on this principle, significantly reduces these impacts. Umbilical artery Doppler reflects downstream placental vascular resistance, strongly correlated with intrauterine growth restriction and the multisystem effects of placental deficiency. Abnormalities are progressive, with reduction, loss, and finally a reversal of diastolic flow. When umbilical arteries become abnormal, the differentiation of fetal status requires Doppler information from systemic vessels. Middle cerebral artery changes begin when the redistribution of cardiac output reflects rising placental resistance, demonstrating 'brain sparing' when cerebrovascular dilation occurs. In the compromised intrauterine growth retarded fetus, precordial veins illustrate fetal cardiac function, changing as the respiratory status declines. This Doppler information is combined with biophysical profile scoring to determine the need for and timing of intervention., Summary: Doppler evaluation of at-risk pregnancies provides crucial prognostic and diagnostic detail about placentation and fetal adaptation. What has been research detail is now becoming the standard of care, in comprehensive fetal-maternal assessment.

Babies who are small due to intrauterine growth restriction are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Through multiple antenatal testing modalities a sequence of deteriorating fetal status can be documented in such cases. The nature of this compromise is best reflected by the combination of fetal biometry, biophysical profile scoring and arterial and venous Doppler. This combination accurately defines fetal states and therefore risk of stillbirth or poor transition to extrauterine life. In the preterm neonate, fetal factors, gestational age and neonatal course interact significantly to impact on short- and long-term outcomes. The potential for iatrogenic prematurity is great and ongoing appraisal of peripartum management is critical. An integrated management protocol accounting for these factors is examined in this review.

The focus of monitoring in diabetic pregnancy is no longer the prevention of fetal mortality, owing to the impressive benefits of strict maternal glucose control. Against this background, fetal monitoring must account for congenital anomalies, fetal mortality and severe morbidity as a result of metabolic consequences of hyperinsulinism, the exponential effect of diabetes when other maternal complications are present, and peripartum problems of the macrosomic infant, of delayed lung maturation, birth trauma and neonatal hypoglycemia. Thus, a broad range of potential fetal problems with varying maternal complications requires individualized, serial observation with multiple-format, properly validated tests. There has been recent progress: definition of the population at risk, clarification of pathophysiology, application of multiple-format tests, and evaluation of neonatal impacts; further precision may be developed with specific fetal tests. This review deals with the continued fine tuning of this critical area of perinatal medicine.